Abstract: Stepped-wedge trial is an emerging cluster randomized controlled trial in the field of service provision and policy evaluation, which is becoming increasingly popular among health care researchers in recent years. There is no need to set up a special control group for stepped-wedge trials, and the advantage of traditional randomized controlled trial is still maintained in the case that the intervention can only be carried out step by step due to limited research resources. In the study, we reviewed the rationale, applicable conditions, characteristics, design types, statistical analysis methods, and relevant reporting guidelines of stepped-wedge trials for providing a reference to quality improvement in stepped-wedge trials and accurate evaluation on health service in real practice.